[pomacea haustrum (reeve, 1856) as a decoy to infection of biomphalaria glabrata (say, 1818) with schistosoma mansoni sambon, 1907]. 1979262318
evaluation of an experimental mollusciciding programme to control schistosoma mansoni transmission in st lucia.the size and number of colonies of biomphalaria glabrata were reduced after four years of a surveillance/treatment snail control programme using an emulsifiable concentrate of niclosamide (25% active ingredient). surveys among the human population showed that the incidence of new schistosoma mansoni infections in 0-10 year-old children fell from 22% to 4.3%, while in a comparison area the incidence remained at 20%. with reduced transmission over four years, the prevalence of infection in a cohor ...1978307443
[fertility of helisoma (seminolina) duryi (wetherby 1879) and biomphalaria glabrata (say 1818), cultured in laboratory (pulmonata, planorbidae)]. 1978549153
host reactions in biomphalaria glabrata to schistosoma mansoni miracidia, involving variations in parasite strains, numbers and sequence of exposures. 1979541169
capacity of irradiated echinostome sporocysts to protect schistosoma mansoni in resistant biomphalaria glabrata. 1979541168
specificity of natural resistance to trematode infections in biomphalaria glabrata. 1979541166
[evaluation of a trial to control biomphalaria glabrata in guadeloupe by using a sterilizing trematode (author's transl)].a trial of biological control of biomphalaria glabrata was carried out in guadeloupe by using ribeiroia marini guadeloupensis nassi, 1978, an autochtonal trematode which sterilizes the snail vector of schistosoma mansoni. the trial took place in a pond in which the population of b. glabrata presents an annual demographic cycle related to the alternation of dry and rainy seasons. about 8 millions eggs of r. marini were introduced in 15 months into the biotope. despite the low yield of these intro ...1979539719
[intestinal schistosomiasis in the freshwater mangrove of guadalupe (french antilles). ecology of the vector, biomphalaria glabrata and its parasite schistosoma mansoni (author's transl)].in the freshwater mangrove of dubelloy-devarieux (guadalupe), the dynamics of populations of b. glabrata and the transmission of s. mansoni, mostly depends on the alternation of dry and rainy season. the flooding of the mangrove (in september), permits a yearly renewal of the malacological populations. the sizes analysis of the snails shows that the life cycle of b. glabrata include two rainy seasons separated by one dry season. the prevalence of b. glabrata (0,25%) and cercariae densities (0,8 ...1979485041
[susceptibility of biomphalaria tenagophila and biomphalaria glabrata to 2 strains of schistosoma mansoni]. 1979482771
comparison of four species of snails as potential decoys to intercept schistosome miracidia.preliminary studies have shown that various species of aquatic snails may be used as decoys or "sponges" to intercept schistosome miracidia, thereby preventing the miracidia from reaching the snails which normally serve as their intermediate host. in this study, four species of snails were evaluated as candidate decoys for field trials: marisa cornuarietis, pomacea australis, helisoma caribaeum, and tarebia granifera. in the laboratory all four species caused considerable reductions in the propo ...1979434319
[differences in the sensilla of african and american cercaria of schistosoma mansoni, the agent of human intestinal bilharziasis].schistosoma mansoni parasite of the human intestinal bilharziasis is frequently transmitted in africa by the snail biomphalaria pfeifferi and in america by biomphalaria glabrata. the comparison between four african strains of cercariae obtained from biomphalaria pfeifferi and five american strains from biomphalaria glabrata points out variations in the number and arrangement of the sensory receptors.1977404049
alterations of the free amino acid content in the hemolymph of biomphalaria glabrata (pulmonata) in starvation and after infection with schistosoma mansoni (trematoda).1. analysing the free amino acid content of the hemolymph of normally fed, starved and schistosome-infected biomphalaria glabrata we identified 22 amino acids and amines, respectively. 2. in comparison with normally fed snails the free amino acid content of starved and infected snails was significantly reduced. 3. however, only slight differences between the ornithine and citrulline content occurred in the three test groups.1979318425
effect of helisoma duryi on the survival, growth, and cercarial production of schistosoma mansoni-infected biomphalaria glabrata.biological control of the intermediate hosts of s. mansoni and s. haematobium by means of a competitor snail,helisoma duryi, has been suggested. in the present laboratory study, information was obtained concerning the interspecific competition between h. duryi and b. glabrata. the results indicated that the growth rate, mortality rate, and cercarial production of s. mansoni-infected b. glabrata were highly influenced by h. duryi. these observations agree with results obtained in earlier experime ...1977303959
the ammonia and urea excretion of biomphalaria glabrata under different physiological conditions: starvation, infection with schistosoma mansoni, dry keeping. 1978299641
[experimental infection of biomphalaria glabrata with schistosoma mansoni in the presence of helisoma duryi]. 1979262314
schistosoma mansoni and biomphalaria glabrata: ultrastructural localization of enzymes with diaminobenzidine in larvae and host digestive glands. 1975235445
bge snail cell-line antigens: ineffectiveness as antischistosomal vaccine in mice.mice and rabbits were immunized with antigens derived from bge cells, biomphalaria glabrata hemolymph, or schistosoma mansoni. antisera from mice given molluscan antigens did not form immunoprecipitates with soluble antigen from adult worms, but their binding to surfaces of sporocysts, cercariae, and schistosomules suggests the presence of cross-reacting determinants. in vitro, cell-mediated immune responses to bge antigens were not demonstrable in infected nor in immunized mice. mice immunized ...1979120433
biomphalaria glabrata: lysozyme activities in the hemolymph, digestive gland, and headfoot of the intermediate host of schistosoma mansoni. 1978103747
immunodiffusion studies on schistosoma mansoni and its intermediate host stage specific antigens. 3. immunoelectrophoresis cross-reactions between s. mansoni stages and biomphalaria sp. hepato-pancreas antigens.immunoelectrophoresis was applied for cross-wise checking of the different stages in the life cycle of schistosoma mansoni with extracts of hepato-pancreas from its intermediate host snails biomphalaria glabrata and biomphalaria alexandrina. only few fractions were common to non infected snail organ and parasite development stage, while more crossreactions were detected with infected snail hepato - pancreas.197877220
immunodiffusion studies on schistosoma mansoni and its host stage specific antigens. 2. immunoelectrophoresis cross-reactions between hepato-pancreas of biomphalaria glabrata and biomphalaria alexandrina.immunoelectrophoresis was used for studies on immunological cross-reactions between both schistosoma mansoni (s. m.) intermediate host snails biomphalaria glabrata and biomphalaria alexandrina. the preparation of antigens and their corresponding antisera from hepato-pancreas of s. m. infected and non infected snails was described as the homologous reactions of both snails either infected or non infected were rather similar, close immunological relationship between b. glabrata and b. alexandrina ...197877219
immunodiffusion studies on schistosoma mansoni and its host stage specific antigens. 1. immunoelectrophoresis cross-reactions between s. mansoni adults and larval stages antigens.immunoelectrophoresis was applied to evaluate the immunologic relationship between the different stages in the life cycle of schistosoma mansoni (s.m.). the preparation of antigens and antisera was described. separated female and male adult worms tested seem to be identical. eggs, miracidia and cercariae from biomphalaria glabrata and biomphalaria alexandrina showed varying degree of cross-reactions. the maximal number of pricipitin arcs was observed, when anti-miracidia-serum was checked agains ...197877218
lectin and human blood group determinants of schistosoma mansoni: alteration following in vitro transformation of miracidium to mother sporocyst.a mixed agglutination assay method was employed to detect the presence of surface determinants for various lectins and human blood group antibodies on schistosoma mansoni miracidia and cultured mother sporocysts. miracidia were found to possess surface receptors for the lectins con a (concanavalin a), anti-heel (eel serum agglutinin), and anti-adb (dolichos seed extract), as well as human anti-a antibodies. following in vitro transformation of the miracidium to mother sporocyst, anti-heel and hu ...197772142
a simple quantitative technique for testing behavioral responses of schistosoma mansoni miracidia to chemicals.we describe a new technique for testing responses of schistosoma mansoni miracidia to chemicals. miracidia in spring water were placed in a chamber shaped like the greek letter phi. small volumes of test chemicals were inoculated into one side of the chamber. after 30 sec a dam was inserted to bisect the chamber and the percentage of miracidia on the inoculated side was calculated. reproducible quantitative results were obtained using the known miracidial stimulants, snail-conditioned water (bio ...197825318
competitive interaction between two snail hosts of schistosoma mansoni: laboratory studies on biomphalaria glabrata and b. straminea. 1979549209
[freshwater snails and vectors of schistosomiasis mansoni in martinique (french west indies)].an inventory of the freshwater molluscs in martinique was worked out during 1972 to 1978. each of the 19 species is shown with its main characteristics. the distribution of biomphalaria glabrata and biompharia straminea was studied. the epidemiological importance of these two snails is discussed.1979575471
effect of schistosoma mansoni infection on fecundity and perivitelline fluid composition in biomphalaria glabrata.egg production in the snail, biomphalaria glabrata, infected with schistosoma mansoni declined on day 23 postinfection, and was significantly lower than uninfected control snails by day 28 and thereafter. protein and galactogen content of eggs produced by infected snails did not change during the period of reduced fecundity. this suggests that decreased hemolymph nutrient levels (rather than depleted albumen gland reserves) are responsible for inhibition of snail egg production. growth rates of ...1979575549
[vertebrate hormones influence on the reproduction of biomphalaria glabrata and on schistosoma mansoni infection (author's transl)].the influence of fifteen vertebrate hormones on the b. glabrata reproduction and on s. mansoni infection have been studied. hecogenine and pregnadienolone significantly increased the snail's number of eggs; testosterone, diethylstilbestrol and estradiol valerianate decreased their number of eggs and the mesterolone and progesterone produced a slight decrease in the number of eggs. crude hecogenine, pregnenolone, prednisone, estradiol, cholic acid, diosgenin, estrone and pregnadione have not show ...1978581097
schistosoma mansoni: susceptibility reversal with age in the snail host biomphalaria glabrata. 1977862703
schistosoma mansoni, echinostoma lindoense, and paryphostomum segregatum: interference by trematode larvae with acquired resistance in snails, biomphalaria glabrata. 1977885213
schistosoma mansoni: temporary reduction of natural resistance in biomphalaria glabrata induced by irradiated miracidia of echinostoma paraensei. 1977891714
[microcalorimetric investigations of the host-parasite relationship between biomphalaria glabrata and schistosoma mansoni (author's transl)].1. the ratio of dry weight to wet weight of infected snails (5.5 +/- 2.2%) is significantly smaller than that of uninfected animals (8.3 +/- 1.0%). 2. the specific values of oxygen consumption and heat-production per dry weight are significantly higher for infected snails (2.41 +/- 0.44 microliter o2/h/mg; 12.63 +/- 1.24 muw/mg) than for uninfected ones (1.88 +/- 0.24 microliter o2/h/mg, 8.94 +/- 0.91 muw/mg). 3. the rate of oxygen consumption always suffices to explain the measured heat flows f ...1977595796
radioisotope labeling of schistosoma mansoni miracidia for in vivo studies in biomphalaria glabrata. 1979501130
schistosome sporocyst-killing amoebae isolated from biomphalaria glabrata. 1979501126
acid phosphatase in granulocytic capsules formed in strains of biomphalaria glabrata totally and partially resistant to schistosoma mansoni. 1977598965
experimental double infection of biomphalaria glabrata snails with angiostrongylus cantonensis and schistosoma mansoni.two groups of biomphalaria glabrata snails primarily infected with angiostrongylus contonensis were secondarily exposed to infection with schistosoma mansoni. to investigate any anatagonistic effect of the first infection on a superimposed one and to compare to singly and non-infected snails, a series of experiments was undertaken in which snails were individually exposed, variously, to 1,000 and 2,000 first-stage larvae of a. cantonensis and then to 5 and 10 miracidia of s. mansoni 1 day and 3 ...1977605654
the predatory activity of lebistes reticulatus (peters, 1859) on schistosoma mansoni miracidia in laboratory experiments.laboratory experiments were conducted to evaluate the role of the guppy, lebistes reticulatus (peters, 1859), as an active predator on schistosoma mansoni miracidia. when five guppies were introduced into 3.5 liters of water containing 500 and 1200 miracidia on two corresponding tests, a dramatic reduction in number of miracidia was observed. in one experiment, no miracidia could be found after 60 minutes of exposure. the infection rates of vector snails, biomphalaria glabrata, exposed to approx ...1977610026
[preliminary study of retriculate varieties of biomphalaria glabrata (say 1818) in comparison with pigmented and albino strains]. 1978653218
effect of manganese on biomphalaria glabrata infected with schistosoma mansoni. 1976977981
[selection in strains of biomphalaria tenagophila and biomphalaria glabrata for improving susceptibility to schistosoma mansoni]. 1978675140
schistosoma mansoni: identification of chemicals that attract or trap its snail vector, biomphalaria glabrata.a new bioassay for chemical attractants of aquatic snails demonstrated that biomphalaria glabrata could be attracted to or trapped in the vicinity of homogenates of lettuce. fractionation of homogenates revealed the amino acids glutamate and proline and the primary attractants. attraction was specific for the l form of glutamate. proline appeared to stimulate reproductive activity. glutathione, gamma-aminobutyric acid, and a number of other compounds had no effect. extracts of lyophilized snail ...1978684418
susceptibility of bahian population of biomphalaria glabrata to an allopatric strain of schistosoma mansoni.seventeen populations of snails (biomphalaria glabrata) from the state of bahia, brazil were studied with respect to their susceptibility to infection with an allopatric strain of schistosoma mansoni. two of the populations were from the city of salvador, 3 from other sites in bahia, and 12 from habitats in the municipio castro alves. our data show that the bahian snail populations are extremely variable in their susceptibility to an allopatric strain of s. mansoni and that the phenomenon is not ...1978686244
an automatic method for recording the emergence of cercariae of schistosoma mansoni from the snail biomphalaria order to study the pattern of emergence of trematode larvae from the snail hosts (s. mansoni from b. glabrata) an automatic apparatus was developed. this apparatus allows the snails, each suspended by a thread, to be transported at intervals of at least half an hour into different beakers into which the cercariae are shed. this "eclosion clock" is essentially a carriage driven on perlon wheels along steel bars.1978695822
[susceptibility of biomphalaria glabrata, albino variant, from belo horizonte, mg, to infestation by schistosoma mansoni, a parasite under natural conditions, of wild rodents of the vale do rio paraiba do sul, sp (brazil)]. 1978715359
schistosoma mansoni: lysozyme activity in biomphalaria glabrata during infection with two strains. 1978729698
hemocytes of biomphalaria glabrata: factors affecting variability. 1978731071
survival and cercaria production of brazilian biomphalaria glabrata and b. straminea infected with schistosoma mansoni. 19751117359
relationship between a species of malaysian nematode daubaylia and the schistosome intermediate host biomphalaria glabrata. 1978749232
[molluscicidal properties of the euphorbia cotinifolia l (author's transl)].the hexanic extract from the leaves of euphorbia cotinifolia l. has been experimentally used as molluscicide against biomphalaria glabrata. the extract was fractionated and the most actives fractions were those of numbers 6 and 7. the lethal concentrations (lc50 and lc90 obtained using fraction 6 against adult snails were 1,2 and 2,4 ppm; for the eggs they were 25,0 and 48,0 ppm. with fraction 7 the lethal concentrations were 1,4 and 3,4 ppm for adult snails; for newly hatched snails they were 4 ...1978751112
[susceptibility of a strain of biomphalaria glabrata from venezuela to infection with 2 different strains of schistosoma mansoni]. 1978751168
[antigenic structure of hemolymph and tissue extract of biomphalaria glabrata infested or not infested with schistosoma mansoni]. 1975819148
in vitro development of schistosoma mansoni cercariae.early cercarial embryos of schistosoma mansoni developed to swimming cercariae within seven days in vitro, via the same sequence of stages as reported in vivo. the presence of living biomphalaria glabrata cells (bge line) was indispensable for proper development. cultured cercariae were water-sensitive, gave no cercarienhüllen reaction, and appeared to lack the surface glycocalyx. further development was not detected in mice or hamsters.1977859081
studies on resistance in snails: a specific tissue reaction to echinostoma lindoense in biomphalaria glabrata snails. 19751201894
studies on resistance in snails: specific resistance induced by irradiated miracidia of echinostoma lindoense in biomphalaria glabrata snails. 19751201896
distribution of the snail biomphalaria glabrata, intermediate host of schistosoma mansoni, within a st lucian field habitat.a total of 6360 mud samples were obtained, in 62 collections made with an exhaustive sampling device, from banana drains on the west indian island of st lucia during fortnightly samplings over a 2(1/2)-year period. analysis of counts of the snail biomphalaria glabrata from these samples showed that this species had a contagious distribution. this finding is consistent with other evidence that banana drains form a rigorous habitat for b. glabrata. its distribution was more contagious than that of ...19751084797
immunoprecipitation and class-specific immunofluorescence titration of human serum antibodies to schistosoma mansoni antigens.twenty sera of individuals with schistosoma mansoni infections were examined by means of immunoelectrophoresis, indirect flourescent antibody (ifa) technique and the defined antigen substrate spheres (dass) system. immunoprecipitins against s. mansoni antigen and against antigen of the intermediate host, biomphalaria glabrata, were demonstrated. the presence of specific anti-s. mansoni iga, igm, igg and ige antibodies were demonstrated. the presence of specific anti-s. mansoni iga, igm, igg and ...19751096483
transaminase levels in the digestive gland-gonad of schistosoma mansoni-infected biomphalaria glabrata. 19751109822
selective depletion of hemolymph proteins of biomphalaria glabrata infected with schistosoma mansoni. 19751117358
schistosoma mansoni miracidial behavior: an assay system for chemostimulation.a new system for evaluating the responses of miracidia to chemostimulants is described. the apparatus consists of a translucent plastic block with a center well and a hole in the edge leading to the well. one end of a glass tube, covered with a dialysis membrane, was inserted into the hole. experimental solutions to be tested were put into the tube and schistosoma mansoni miracidial behavior was observed in the well on the other side of the permeable membrane. miracidia were released near the me ...19751127550
genetic studies on variation in infectivity of schistosoma mansoni.biomphalaria glabrata snails of known genetic susceptibility types were exposed to miracidia from 2 strains of schistosoma mansoni differing in infectivity.. individual snails were exposed to single miracidia and penetration observed. snails of a genetic type susceptible to both parasite strains served as controls, while snails of a genetic type susceptible to one parasite strain but relatively refractory to the other served as test snails to demonstrate the difference in parasite infectivity. ...19751127551
[castration of the snail biomphilaria glabrata by the larvae of various guadeloupean trematoda].four species of trematoda accomplish their larval development in the snail biomphalaria glabrata. they determine the sterility of the mollusc in different ways and could be used in the biological control of schistosomiasis resulting from schistosoma mansoni.1975811375
rats and bilharziasis in guadeloupe.the rats in guadeloupe (rattus rattus and rattus norvegicus) may play a part in schistosomiasis in three ways: - by harbouring fertile s. mansoni, a fact which serves to increase the total population of the parasite and may eventually take part in the infestation of man; - by harbouring a great number of ribeiroia marini, a trematode whose larval stages sterilize biomphalaria glabrata, the vector of schistosomiasis; - simply by eating b. glabrata. the quantitative influence of these contradicto ...19757114
intraspecific variations in the hemolymph of biomphalaria glabrata, a snail host of schistosoma attempt was made to characterize the hemolymph of biomphalaria glabrata with reference to "normal" intra-specific variation, i.e., both inter- and intra-strain differences. total protein concentration, per cent hemoglobin, ph, and osmolarity were studied. seven geographic strains of b, glabrata were examined. in addition, observations were made on the hemolymph of biomphalaria straminea, several strains of helisoma caribaeum, and on b. glabrata subjected to infection with schistosoma mansoni ...19753698
[ammonium- and urea concentration in the hemolymph of biomphalaria glabrata infected with schistosoma mansoni]. 19751130133
studies on resistance in snails: interference by nonirradiated echinostome larvae with natural resistance to schistosoma mansoni in biomphalaria glabrata. 1977850073
[experimental schistosomiases. i. study of s. mansoni fecondity as regards to its adaptation to different biomphalaria glabrata strains (author's transl)].we compared the infestation of different strains of b. glabrata from brasil (recife). guadeloupe, martinique and porto-rico with 6 to 8 miracidia of s. mansoni (from recife. we noted the four following points: 1. the planorbid snails from martinique and guadeloupe had a low resistance to infestation. 2. the guadeloupean snails showed the lesser rate of positivity and the lower medium amount of emitted cercaries but, in the four strains of snails, the level of the issued cercaries is quite the sa ...19751221915
control of schistosoma mansoni transmission by chemotherapy in st. lucia. ii. biological results.chemotherapy of all persons infected with schistosoma mansoni was begun in marquis valley, st. lucia, in march 1974. from january 1972 to the start of chemotherapy, the infection rate in field biomphalaria glabrata collected in the valley was 1.09% (117/10,736) and the rate in sentinel b. glabrata was 1.48% (56/3,790). from march 1974 through december 1975, no infections were detected in either field snails (11,742 collected) or sentinel snails (3,230 exposed). the accumulated date suggest that, ...1977907052
[the ketone bodies in the hemolymph of biomphalaria glabrata under starvation and infection with schistosoma mansoni (author's transl)].the metabolism of the snail biomphalaria glabrata stressed by five days' starvation as well as by infection with schistosoma mansoni was examined with regard to the metabolism of ketone bodies. previous studies in the metabolism of this host--parasite relationship always resulted in changes in the same direction with starvation as well as with infection. contrary to that the concentration of acetoacetate and beta-hydroxybutyrate measured in the hemolymph decreased significantly with starvation b ...1977919681
[natural transmission of schistosoma mansoni in guadeloupe (french antilles). preliminary note (author's transl)].occasioning in guadeloupe a high rate of morbidity, schistosomiasis is unequally spread in the field. the intermediate host, biomphalaria glabrata, is wide-spread. but some biotopes only, most of them located on the coast belt of the montainous island, allow the parasite growth. among them, the irrigation canals appear as the most dangerous source of contamination for human population.1977921190
[principal factors involved in the settlement of biomphalaria glabrata (say, 1818), snail intermediate host of schistosomiasis in guadalupe (author's transl)].six biotopes of biomphalaria glabrata, the snail intermediate host of schistosomiasis in guadalupe, were investigated during one annual cycle. these six biotopes included a pond, a freshwater mangrove, a stream, a mountain lake, a "microhabitat" and a canal. these six types of biotopes were characterized by various parameters whose fluctuations reveal the main factors regulating the b. glabrata populations. the climatic factors are essential in grande terre and resulted in an annual development ...1977921191
[factors responsible for cercarial concentration of schistosoma mansoni in guadeloupe].research carried out in guadeloupe on the sites of transmission of schistosoma mansoni shows that the circadian evolution of the cercarial concentration (rhythm of presence) differs slightly according to the biotope:--in a running water habitat (greater than 0,10 m/s) the rhythm of presence is superimposed on the rhythm of emergence, which leads to a risk of contamination reaching a maximum between 11 a.m. and noon; --in a slow running water habitat (around 0,01 m/s), the acrophase of the rhythm ...1977931320
the karyotype of biomphalaria glabrata, the snail vector of schistosoma mansoni.karyotyping was done on the mitotic metaphase chromosomes obtained from the embryos of biomphalaria glabrata. the 18 chromosome pairs were identified and classified into 6 groups. the diploid cell has 10 pairs of metacentric, 4 pairs of submetacentric, 2 pairs of acrocentric and 2 pairs of telocentric chromosomes. the pair number 8 with secondary constriction can be used as a marker in genetic experiments.1976948208
studies on resistance in snails. 7. evidence of interference with the defense reaction in biomphalaria glabrata by trematode larvae.echinostoma lindoense sporocysts that develop from irradiated miracidia normally are destroyed by amebocyte capsules in the ventricle of biomphalaria glabrata within 10 days postexposure. the survival period of these ventricular sporocysts was considerably longer in snails that also harbored normal sporocysts of e. lindoense, paryphostomum segregatum, or schistosoma mansoni. protection of irradiated e. lindoense sporocysts by the same of different trematode species is presumed to be the result o ...1976957039
[french guiana and bilharziasis].the authors discuss about the lack of bilharziasis in french guyana and report the experimental infestation of biomphalaria glabrata coming from cayenne with a porto-rican strain of schistosoma mansoni.19761037435
histologic and cytochemical observations of the effects of schistosoma mansoni on biomphalaria glabrata. 19751072600
[cell culture of snails. their use in the study of immunologic host-parasite relationships in schistosomiasis].the host-parasite relationship between schistosoma mansoni and the snail biomphalaria glabrata is so complex that its experimental study needs some particularly working methods: for instance molluscan organs and tissue's cultures. in the experiment described we report that digestive gland's cells cultures were grown on synthetic cultural medium. this one contained a physiological salt solution and a basal nutrient medium consisting of foetal calf serum, chicken embryo extract and amino-acids. in ...19751243880
variations in infectivity for biomphalaria glabrata in strains of schistosoma mansoni from the same geographical area.genetic differences in infectivity for intermediate snail hosts in two strains of s. mansoni from the same geographical area and within a single isolated parasite population are reported. the importance of recognizing the potential for such genetic variation is stressed.19761088517
intramolluscan trematode antagonism in a genetically susceptible strain of biomphalaria glabrata. 19761262123
immunoelectrophoretic study on common antigens of são lourenço da mata and belo horizonte strains of schistosoma mansoni adult worms and biomphalaria snails.immunoelectrophoretic studies on common antigens were carried out by using rabbits sera immunized against são lourenço da mata and belo horizonte strains of schistosoma mansoni adult worms and antigens of biomphalaria glabrata pigmented (jaboatão--pe); b. glabrata albino (belo horizonte--mg) and b. straminea (são lourenço da mata, pe). furthermore, the reverse approach was proceeded, namely, sera anti biomphalaria snails produced in rabbits were tested against both strains of schistosoma adult w ...19921284896
immunosuppression in the definitive and intermediate hosts of the human parasite schistosoma mansoni by release of immunoactive neuropeptides.evidence supporting the concept that the parasitic trematode schistosoma mansoni may escape immune reactions from its vertebrate (man) or invertebrate (the freshwater snail biomphalaria glabrata) hosts by using signal molecules it has in common with these hosts was obtained by the following experiments. the presence of immunoactive proopiomelanocortin (pomc)-derived peptides [corticotropin (acth), beta-endorphin] in, and their release from, s. mansoni was demonstrated. coincubation of adult worm ...19921309957
superinfection of biomphalaria glabrata with schistosoma mansoni.biomphalaria glabrata 2 to 12 mm in diameter were exposed to 1 miracidium of schistosoma mansoni and after 15, 30, or 60 days were reexposed to the homologous strain. the criterion of superinfection was the subsequent escape of cercariae of both sexes. opposite sex superinfection was acquired by 45 of 106 snails of various sizes, all of which were in the group reexposed at 30 days. the observations confirm those of kagan and geiger and suggest that in the schistosomes a maximizing of the number ...19751117376
carbohydrate-binding plasma proteins from the gastropod biomphalaria glabrata: strain specificity and the effects of trematode lectins are believed to mediate non-self-recognition in molluscs, carbohydrate-binding proteins (cbp) from the circulating plasma of the gastropod biomphalaria glabrata were harvested by affinity chromatography using six different monosaccharides as ligands. pools of plasma were derived from b. glabrata of either the m line strain, which is susceptible to infection with the pr1 strain of the digenetic trematode schistosoma mansoni, or from the 13-16-r1 strain, which is resistant to infection. ...19921330758
the prolonged use of niclosamide as a molluscicide for the control of schistosoma mansoni.applications of niclosamide at three-monthly intervals were undertaken for 14 years in foci of biomphalaria glabrata in the water sources of peri-peri (capim branco, mg). all the residents of the area were submitted to an annual fecal examination (kato/katz) and those individuals eliminating schistosoma mansoni eggs were treated with oxamniquine. a malacological survey was undertaken at three-monthly intervals by means of ten scoops with a perforated ladle each ten metres along the two banks of ...19921342106
genetic factors in susceptibility of biomphalaria glabrata for different strains of schistosoma mansoni.biomphalaria glabrata selected for genetic differences in susceptibility to infection with a puerto rican strain of schistosoma mansoni were exposed to miracidia of a strain of s. mansoni from st lucia. the st lucian strain was less infective than the puerto rican. results suggested that in snails susceptible to the puerto rican s. mansoni differences in susceptibility to the st lucian straing were determined by a single gene, with insusceptibility dominant.19751128925
immunodiagnosis of human schistosomiasis using different immunoprecipitation hundred sera of individuals infected with schistosoma mansoni and/or s. haematobium were examined for the presence of specific anti schistosoma antibodies by means of different immunoprecipitation techniques: immunoelectrophoresis, immunodiffusion, immunoelectroosmophoresis (on two different supports), and electroimmunodiffusion. the immunoelectroosmophoresis proved to be superior to the other immunoprecipitation techniques, its main advantages being sensitivity, rapidity, and economic use o ...1975810988
intermediate hosts of schistosoma mansoni in brazil.the brazilian planorbidical chart is slowly but progressively been increased by new data. distribution of vector species of schistosoma mansoni, according to paraense, 1986, may be thus resumed: biomphalaria glabrata--delimited by parallels 13 and 21 degrees s and meridians 39 and 45 degrees w, area of greater dominance (southeast bahia, oriental hal of minas gerais and espírito santo). it is observed along the coast line of the states of sergipe, alagoas, pernambuco, paraiba and rio grande do n ...19921343914
miracidium of schistosoma mansoni: a macromolecular glycoconjugate as signal for the behaviour after contact with the snail host.1. the behaviour of the miracidium of schistosoma mansoni after contact with agar blocks containing biomphalaria glabrata snail conditioned water (scw) or its components, was studied. 2. "repeated investigation" was the most specific response at contact with the snail host. 3. fractionation and specific chemical treatment of scw revealed that this response was stimulated by a lysozyme sensitive glycoconjugate with a mol. wt greater than 300,000. 4. low molecular weight components of scw had no s ...19921348464
studies on common antigenicities between the belo horizonte strain, brazil of schistosoma mansoni eggs and biomphalaria snails by immunoelectrophoresis.immunoelectrophoretic studies of common antigenicities were carried out by using rabbit sera immunized against the belo horizonte strain of schistosoma mansoni eggs and crude antigens of biomphalaria snails and vice versa. with regard to common antigenicities between s. mansoni eggs and biomphalaria snails, s. mansoni eggs produced 4 to 5 bands with biomphalaria glabrata pigmentado, 3 to 4 bands with b. glabrata albino and only 1 band with b. straminea. in our laboratory, the infection rate of s ...19921381846
responses of echinostoma caproni miracidia to gravity, light, and a four-tube vertical system, echinostoma caproni miracidia exhibited a strong negative geotaxis which was dominated by a positive phototaxis. in horizontal chambers a positive phototactic response was also demonstrated. these miracidia showed a positive chemoresponse, as determined in phi-chambers, to glutamic and aspartic acids but not leucine. positive responses were also elicited to snail-conditioned water and sulfuric and acetic acids. ammonia, mg2+, and hcl produced no significant reacti ...19921399253
schistosoma mansoni infection in diapausing biomphalaria glabrata snails: studies of temperature and genetic influences on diapausing behavior.snails that are capable of undergoing diapause can circumvent unfavorable environmental conditions, including long periods of drought. studies were performed to investigate possible temperature and/or genetic factors that may trigger lamella formation and diapausing behavior. the influence of diapause in biomphalaria glabrata snails on susceptibility to schistosoma mansoni infection and levels of cercarial production was also investigated. rearing temperatures of 23 degrees c or higher did not i ...19921443349
early enhanced growth of the digestive gland of biomphalaria glabrata infected with schistosoma mansoni: side effect or parasite manipulation?we carried out a comparative study of the dynamics of the sporocyst population and the growth rate of the host habitat (digestive and genital gland) within the schistosoma mansoni/biomphalaria glabrata system during monomiracidial infections. the volume of the digestive gland increased sharply during the first 2 weeks of infection and then decreased at 2-4 weeks post-infection during the exponential growth phase of the sporocyst infrapopulation. the effects of the parasite on the development of ...19921495925
echinostoma paraensei and schistosoma mansoni: adherence of unaltered or modified latex beads to hemocytes of the host snail biomphalaria glabrata.hemocytes derived from a strain (13-16-r1) of biomphalaria glabrata resistant to schistosoma mansoni were significantly more likely to bind untreated latex beads than hemocytes from the schistosome-susceptible m line strain. beads preincubated in 13-16-r1 plasma were more readily bound by both 13-16-r1 and m line hemocytes than beads preincubated in m line plasma. beads preincubated in plasma derived from snails of either strain infected with the trematode echinostoma paraensei were more readily ...19921516670
biological control of the snail intermediate hosts of schistosoma mansoni in martinique, french west martinique water-cress beds constituted the last transmission sites for schistosomiasis. the competitor snail, melanoides tuberculata, was introduced at the beginning of 1983 to a group of water-cress beds and eliminated the snail hosts, biomphalaria glabrata and b. straminea, in less than two years. following this first success, m. tuberculata was introduced to the other groups of beds which were inventoried at the beginning of the eighties. at the present time, b. glabrata and b. straminea ...19921519033
a comparison of the glycolipid compositions of cercarial and adult schistosoma mansoni and their associated hosts.glycolipid patterns of cercarial and adult schistosoma mansoni were determined and compared with those of biomphalaria glabrata snails and mouse (balb/c strain) red blood cells by high-performance thin-layer chromatography. differences in glycolipid content were found between cercariae and adult worms and between these stages and their respective host tissues.19902074137
spatial and energy compromise between host and parasite: the biomphalaria glabrata-schistosoma mansoni system.the development of a sporocyst infrapopulation of schistosoma mansoni within the biomphalaria glabrata snail is, from a spatial point of view, detrimental to the host's digestive-genital gland complex growth. for mono- and plurimiracidial infections, the digestive gland volumes are, respectively 51 and 24% of those of control snails. identical reduction of the infected genital gland volume (43% of controls) occurs in both cases. after the prepatent period, the ratio of parasite/digestive gland v ...19921563925
schistosoma mansoni infections in neonatal biomphalaria glabrata areas endemic for schistosomiasis, the population dynamics of the snail intermediate hosts have a direct effect on parasite transmission. the present study focused on the potential for neonatal biomphalaria glabrata snails to become infected with schistosoma mansoni and to produce cercariae under various conditions. it was found that snails as small as 0.74 mm in shell diameter could survive miracidial penetration and could release cercariae when as small as 1.6 mm in diameter. cercariae prod ...19921597786
identification, comparison and partial characterization of glycoproteins in the hemolymph of schistosoma mansoni (trematoda)-susceptible and resistant biomphalaria glabrata (gastropoda).1. glycoproteins in the plasma (cell-free hemolymph) of schistosoma mansoni-resistant and susceptible strains of biomphalaria glabrata were identified, characterized and compared using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, electroblotting and a series of peroxidase-labeled lectins with different sugar specificities. 2. schistosome-resistant snails possessed at least three glycoproteins (70, 116, 205 kda) that were not present in plasma from susceptible snails. 3. sporocysts ...19921617939
biomphalaria glabrata: influence of calcium, lectins, and plasma factors on in vitro phagocytic behavior of hemocytes of noninfected or schistosoma mansoni-infected vitro phagocytosis of erythrocytes by hemocytes of b. glabrata, intermediate host of s. mansoni, is strongly influenced by calcium, several lectins, and plasma factors. our results indicate that two different mechanisms of non-self-recognition in b. glabrata may occur: (1) in the presence of calcium, phagocytosis occurs in noninfected and in infected snails without involvement of any other substances, and hemocytes of schistosome resistant as well as those of susceptible snails are able to re ...19921639158
identification of a schistosoma mansoni sporocyst excretory-secretory antioxidant molecule and its effect on superoxide production by biomphalaria glabrata hemocytes.excretory-secretory (e-s) products obtained during in vitro schistosoma mansoni miracidium-to-sporocyst transformation were found to contain a 108-kda polypeptide capable of scavenging both exogenously produced and m-line biomphalaria glabrata hemocyte-derived superoxide (o2-) anions. separation of crude transformation e-s products using hplc and ion exchange chromatography resulted in the separation of two isoforms of the 108-kda molecule. using an in vitro phagocytosis assay, both isoforms wer ...19911664845
schistosoma mansoni: use of a cloned ribosomal rna gene probe to detect restriction fragment length polymorphisms in the intermediate host biomphalaria susceptibility of biomphalaria glabrata to schistosoma mansoni infection is controlled by simple mendelian genetics. in this study a molecular approach was used to determine the degree of genetic variation between well-defined lines of b. glabrata which are either resistant (10-r2) or susceptible (m-line) to s. mansoni infection. a cloned probe psm389, which contains part of the s. mansoni small ribosomal rna gene and a portion of the nontranscribed spacer was found to cross-hybridize with ...19911680745
schistosoma mansoni and biomphalaria glabrata have some common epitopes. i. common epitopes are present on the surface of early stages of s. mansoni.1. the presence of snail and glycocalyx antigens in the schistosoma mansoni cercarial surface and their permanence throughout development in vitro and in vivo was investigated. 2. rabbit antisera raised against two fractions of glycocalyx released from cercariae and biomphalaria glabrata soft tissues or haemolymph were obtained. 3. all four antisera bound to cercariae and schistosomula kept in vitro or in vivo for up to 24 hr. 4. no binding to schistosomula kept in vivo for 5 days or longer was ...19911726079
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